I. Field of the Invention
The present invention relates generally to liners for nurser bottles. More particularly, the present invention relates to tabs located at an open end of a flexible liner, particularly disposable liners, that are designed to facilitate opening the mouth of the liner and mounting of the liner onto a rigid nurser bottle or holder. Furthermore, the particular textured tabs have a tactile feel that improve gripping during opening and mounting of the liner.
Disposable liners for containing liquids have been used with rigid holders to provide a clean, sanitary container for each use instead of reusable bottles which require regular washing and sometimes give questionable results regarding cleanliness. Typically, a liner is mounted onto a holder by gripping the upper edge of the liner, drawing the edge over an open rim of the holder, and folding the edge downward over the outer surface of the holder. The liner is then filled with a desired liquid, and a cover, such as a nursing nipple, may be attached to the holder to close the mouth of the liner.
In order to maintain cleanliness, tabs may be located at the mouth of the liner to provide finger grasp positions. The tabs theoretically permit one to firmly grasp the liner to facilitate opening of the mouth of the liner. The tabs also permit one to draw the liner over the rim of the holder, without one's hands contacting the inside of the liner. The tabs may even be adapted to separate from the liner by the use of perforations once the liner has been mounted on the holder.
It is now appreciated that gripping each tab may be difficult if there is no texturing on the surface of each tab. Moreover, the texturing itself and its placement on the tab's surface will affect the gripability of each tab.
II. Description of the Prior Art
Disposable nurser liners having a graspable flange at the mouth of the liner are known. For example, U.S. Pat. No. 3,204,855 to I. D. Boynton, which issued on Sep. 7, 1965 titled Flexible Container and U.S. Pat. No. 3,790,017 to W. E. Fitzpatrick, et al., which issued on Feb. 5, 1974 titled Nursing Unit, each provide a nurser liner having a pair of hand-graspable tabs at the mouth of the liner to facilitate assembly of the liner in a rigid nurser holder. Each tab has large, smooth surfaces that may be easily grasped between one's thumb and fingers. Thus, the tabs facilitate opening the mouth of the liner and drawing it over the open rim of the holder.
Other examples of nurser products having flexible flanges to facilitate handling and use of the products are provided in U.S. Pat. No. 2,460,329 to A. M. Allen, et al., which issued on Feb. 1, 1949 titled Nursing Unit; U.S. Pat. No. 2,624,485 to F. E. Boston, which issued on Jan. 6, 1953 titled Nurser; U.S. Pat. No. 2,859,891 to G. V. Carkin, which issued on Nov. 11, 1958 titled Nursing Bottle; U.S. Pat. No. 2,881,935 to W. P. Garred, which issued on Apr. 14, 1959 titled Infant's Nursing Bottle Assembly; U.S. Pat. No. 2,939,598 to T. J. Donleavy, which issued on Jun. 7, 1960 titled Dispensing Container; U.S. Pat. No. 3,395,822 to T. J. Donleavy, which issued on Aug. 6, 1968 titled Nursing Device; U.S. Pat. No. 3,645,414 to A. C. Barr, which issued on Feb. 29, 1972 titled Nursing Unit With Improved Plastic Liner; U.S. Pat. No. 3,762,542 to G. S. Grimes, which issued on Oct. 2, 1973 titled Infant Feeding Means; U.S. Pat. No. 3,871,542 to I. M. Hammer, which issued Mar. 18, 1975 titled Disposable Nursing Container; and U.S. Pat. No. 4,711,359 to L. A. White, et al., which issued Dec. 8, 1987 titled Container Such as a Nursing Container, Having Protection Compartment For Dispensing Member.
One problem with the nurser liners of the above patents is that the surfaces of the tabs are smooth and, thus, a firm grasp of the tabs is difficult to attain. In particular, one must hold each tab between his or her thumb and fingers with significant pressure. Accordingly, one or both tabs may slip out from between one's thumb and fingers so that assembly of such nurser liners in a rigid holder is difficult.
In addition to nurser liners, there are also other flexible containers or bags having handles or tabs to facilitate handling and use. Several of these non-nurser products have embossed surfaces to facilitate opening and handling of the product. For example, U.S. Pat. No. 2,197,113 to T. E. Piazze, which issued Apr. 16, 1940 titled Bag Assemblage, provides a bag for packaging merchandise having two walls and a textured zone, located at an upper portion of each wall, that is indented, corrugated, embossed or roughened in order to facilitate the opening or spreading of the upper portions. Also, U.S. Pat. No. 3,224,574 to A. L. McConnell, et al., which issued on Dec. 21, 1965 titled Embossed Plastic Bag, and U.S. Pat. No. 3,411,698 to W. G. Reynolds, which issued Nov. 19, 1968 titled Bag-Like Container Means, each provide embossing the walls of a bag for food products to facilitate the grasping and separating of the bag's walls.
Other examples of non-nurser products having handles or tabs to facilitate handling and use of such products are provided in U.S. Pat. No. 3,148,799 to A. H. Meroney, which issued Sep. 15, 1964 titled Disposable Adjustable Receptacle Liner For Wet Refuse; U.S. Pat. No. 3,166,220 to S. W. Rabb, et al., which issued on Jan. 19, 1965 titled Dispensing Holder and Receptacle; U.S. Pat. No. 3,170,619 to J. P. Repko, which issued on Feb. 23, 1965 titled Tear Strip Packaging; U.S. Pat. No. 3,393,861 to W. J. Clayton, et al., which issued Jul. 23, 1968 titled Embossed Thermoplastic Bags; U.S. Pat. No. 3,441,198 to A. E. Ericson, which issued Apr. 29, 1969 titled Flexible Bag For Packaging Food Items; U.S. Pat. No. 3,534,901 to J. P. Repko, et al., which issued on Oct. 20, 1970 titled Bag Construction; U.S. Pat. No. 3,550,839 to W. J. Clayton, which issued Dec. 29, 1970 titled Doubled Walled Plastic Bag; U.S. Pat. No. 3,873,735 to M. L. Chalin et al., which issued on Mar. 25, 1975 titled Food Package For Heating and Venting; U.S. Pat. No. 4,509,570 to J. Eby, et al., which issued Apr. 9, 1985 titled Elastic Top Bag; U.S. Pat. No. 4,524,457 to F. J. Marino, which issued on Jun. 18, 1985 titled Cargo Bag With Reinforced Triangular Lifting Panels; U.S. Pat. No. 4,747,701 to S. Perkins, which issued May 31, 1988 titled Plastic Liner Bag With Elastic Top and Method of Making; U.S. Pat. No. 4,549,657 to A. M. Martin, which issued on Oct. 29, 1985 titled Easily Opened and Reclosable Bag and Apparatus For Making Same; U.S. Pat. No. 4,759,639 to R. B. DeMatteis, which issued on Jul. 26, 1988 titled Thermoplastic Bag; and U.S. Pat. No. 4,769,126 to R. M. Roen, et al., which issued Sep. 6, 1988 titled Bottom Gusset Bag Pad Arrangement For Liquid Containers.
Since these containers and bags are not nurser liners, they are not suited for mounting on nurser bottles. Although several of these containers and bags have embossed surfaces, such embossed surfaces do not provide adequate gripping surfaces for nurser liners. In particular, the above patents do not describe or suggest gripable tabs that permit one to draw them over an open rim of a rigid holder and fold them downward over the outer surface of the holder. This operation of assembling the nurser liner in a rigid holder requires a significantly tight grip to prevent the tabs from slipping out of one's hands and to facilitate assembly in the holder.
A disposable nurser liner having a gripable embossed tabs at the mouth of the liner is shown in U.S. Pat. No. 5,385,251 to S. B. Dunn, which issued on Jan. 31, 1995, titled Disposable Bottle Bags For Use With Infant Nursing System. This patent provides a nurser liner having integrally embossed surfaces adjacent to the mouth of the liner to facilitate the separation of adjacent surfaces at the liner's mouth. This patent also provides another embodiment having a half-circular finger hole in the middle of each tab and a further embodiment having a combination of the embossed surfaces and the half-circular finger hole. However, these embossed tabs have poor gripping surfaces. Also, the half-circular finger hole significantly reduces the surface area of the tabs and, thus, provide less surface area for one to grip. Further, the nurser product distributed by the assignee of U.S. Pat. No. 5,385,251, namely Munchkin Bottling Inc. of Van Nuys, Calif., has the combination of the embossed surfaces and the half-circular finger hole. Therefore, it appears that the embossed surfaces require the finger holes to provide an adequate grip. Also, the combination of these two features obviously makes manufacturing more time consuming and, therefore, costly.
Another problem with the nurser liner of the above patent is that embossing the tabs and/or the addition of finger holes hinders one's capability to open the mouth of the liner. For example, the liner's mouth may be opened by gripping the middle portion of each tab between one's finger and thumb and sliding them past one another. This process distorts the mouth of the liner and separates the tabs so that each tab may be gripped by each hand of a person. By embossing the tabs, the friction between the adjacent surfaces of each tab increases so that it is more difficult to slide the tabs past one another. Also, the creation of finger holes in the tabs reduces available surface area and, particularly, the most convenient surface of the tabs to grip, i.e., the middle portion. Thus, a finger hole further hinders opening of the liner mouth.
A gripable surface that provides a sufficient grip to prevent the tabs from slipping out of one's hands and to facilitate assembly in the holder is provided in co-pending parent application Ser. No. 08/317,244 cited above, which application is owned by the assignee of the present invention. Specifically, each tab of the nurser liner has a plurality of ruptured areas formed by completely piercing through the tab all of the time. By piercing, the completely pierced through or ruptured areas form a tactile surface to facilitate gripping of each tab. Also, each tab has the pierced through surface on the same side so that the mating surfaces of the pair of tabs have different features to facilitate separation. Accordingly, the pierced tabs of the above co-pending parent application provide a tactile surface that is better and easier to grip than embossed surfaces or finger holes. Moreover, it is easier to separate the adjacent tab surfaces.
However, it has been determined that the piercing tools used to pierce through the tabs one hundred percent of the time become dull relatively quickly. Thus, the manufacturing cost of the nurser liners having one hundred percent piercing increases due to the cost of replacing worn or dull piercing tools. In particular, the replacement cost includes the actual cost of the tools, the labor cost of replacing the tools, and the production time lost until replacement. Therefore, the present invention provides a nurser liner having the gripping advantages of pierced tabs, as described in the above co-pending parent application, while extending the service life of the piercing tools.